Illegal reintroductions of rare butterflies to UK ‘a risk to other species’

The black-veined white, a species which fell extinct in Britain 100 years ago, and has now reappeared on a nature reserve near Croydon. Photograph: Adam Gor/Butterfly Conservation/PA

“Ridiculous” illegal reintroductions of rare or extinct butterflies to new sites in Britain risk introducing disease, damage attempts to save species and jeopardise well-planned releases, conservationists have warned.

Conservation scientists spoke out after black-veined whites, which fell extinct in Britain 100 years ago, reappeared on a nature reserve near Croydon.